Differential Diagnosis for Chronic Cough Not Responding to Antibiotics

• Single Most Likely Diagnosis
  • Gastroesophageal reflux disease (GERD): This is a common cause of chronic cough, especially when it doesn't respond to antibiotics. The stomach acid can irritate the throat and lungs, leading to a persistent cough.
• Other Likely Diagnoses
  • Asthma: Chronic cough can be a symptom of asthma, even in the absence of wheezing or shortness of breath. The cough can be dry or productive and may worsen at night or with exercise.
  • Allergic rhinitis: Postnasal drip from allergic rhinitis can cause a chronic cough. This is often accompanied by other symptoms like sneezing, runny nose, and itchy eyes.
  • Chronic obstructive pulmonary disease (COPD): COPD can cause a chronic cough, often productive of mucus, due to the chronic inflammation and damage to the lung tissue.
• Do Not Miss Diagnoses
  • Lung cancer: Although less common, lung cancer can present with a chronic cough that doesn't respond to antibiotics. It's crucial to consider this diagnosis, especially in smokers or those with a significant smoking history.
  • Tuberculosis (TB): TB is another critical diagnosis not to miss. It can cause a chronic cough, often accompanied by weight loss, night sweats, and fever.
  • Pulmonary embolism: While less common, pulmonary embolism can cause a sudden onset of chronic cough, often accompanied by shortness of breath and chest pain.
• Rare Diagnoses
  • Sarcoidosis: This is a rare disease that can cause inflammation in various parts of the body, including the lungs, leading to a chronic cough.
  • Cystic fibrosis: Although more common in children, cystic fibrosis can also present in adults with a chronic cough, productive of thick, sticky mucus.
  • Bronchiectasis: This condition involves the permanent enlargement of parts of the airways and can cause a chronic cough, often productive of large amounts of mucus.